Examples of prior art aircraft sleeper seats are disclosed in the applicant's patent publications WO-A-9618537 and WO-A-0021831, embodiments of which include the current British Airways First and Club World seats respectively. Both of these seats can be converted into a flat, horizontal bed, and have enjoyed great commercial success. However, there is intense competition to provide ever-greater comfort and space for aircraft passengers.
Passenger seats for aircraft are subject to stringent design constraints, many of which are not applicable to seats for other vehicle types. One problem is the need to meet the relevant safety standards for aircraft passenger seats, such as the 16 g test that requires seats to survive deceleration of 16 g in a takeoff/landing position. Another problem is the need to minimize the weight of the seat, since carrying extra weight on an aircraft increases fuel consumption and therefore monetary and environmental cost. Hence, the seat must be both strong and light.
Another problem relates to the use of space. Any given aircraft has a maximum area for passenger seating, which must be used in the most space-efficient manner possible so as to maximize the seating area and legroom available to each passenger, while allowing unimpeded exit from the seat. It is also important for cost reasons to fit as many passenger seats as possible in the available area.
Another problem relates to the level of comfort of the seat. Aircraft passenger seats may be used for day flights, in which the passenger will want to work, eat and/or relax, and night flights during which the passenger will want to sleep. Preferably, an aircraft passenger seat should be able to adopt comfortable positions for all of these activities, yet also be able to meet the relevant safety standards in a takeoff/landing position.
Another problem relates to the psychological and/or social needs of aircraft passengers, who may desire privacy while working, eating or sleeping, or may wish to interact with a travelling companion. There are also some arrangements that are undesirable for aesthetic and/or psychological reasons; for example, it is preferred that parts of the seat mechanism are not visible to the passenger.
In first class seats, the passenger demands the greatest possible level of comfort and it is accepted that fewer passenger seats will be accommodated in the available area than would be the case for economy or business class. For first class sleeper seats, it is desirable to provide a sleeping arrangement that is as close as possible to a normal bed. However, normal single beds are considerably wider than an aircraft passenger seat needs to be.
One approach to this problem has been to provide armrests that retract so as to be level with the seat in a fully reclined position, so that the width of the armrests is added to the seat width. One such arrangement is disclosed in Patent publication no. WO 98/36967 (Singapore Airlines).
Another approach to this problem can be seen in the Odyssey™ aircraft seat disclosed at http://www.flatseats.com/Product/news-contour-3108.htm on 28 Oct. 2005 or earlier, and described in an article in the London Evening Standard on 8 Jul. 2005. As shown schematically in FIG. 1, the arrangement comprises a bed surface 1 adjacent to one side of a reclining seat 2. One disadvantage of this arrangement is that the seat pitch, i.e. the spacing between adjacent rows of seats, is very short and so legroom is restricted. Also, the bed surface 1 takes up a great deal of space so it is not practicable to increase the seat pitch as this leads to very inefficient use of space. Another problem is that the seat 2 does not provide a deep reclined position suitable for resting. Another problem is that the passenger has to adopt a completely different position when sleeping than when sitting, and so has to rearrange personal effects, bedding, cushions and the like when moving from the sitting to sleeping position.